Graphene oxide-silver nanocomposite (GO-Ag) was fabricated via the sonochemical method, which shows unique physiochemical properties. Graphene oxide (GO) and silver nanoparticles (AgNPs) were synthesized by modified Hummer's and Chemical reduction methods, respectively. The synthesized nanocomposite was characterized using powder X-ray diffraction, Raman spectroscopy, and Fourier-transform infrared spectroscopy. The surface morphology of synthesized nanoparticles was studied using scanning electron microscopy and transmission electron microscopy. The thermoluminescence property of the nanocomposite was analyzed by irradiating the samples in gamma radiation at 1 kGy. Electrochemical reversibility of the GO-Ag nanocomposite was examined by cyclic voltammetry. The photocatalytic application of the nanocomposite was studied using degradation of methylene blue dye. Results reveal that doping of AgNPs on the GO surface not only improves its dye degradation property but also enhances its thermoluminescence property. This knowledge will be helpful in determining the antibacterial property of the GO-Ag nanocomposite in the future.

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Dengue is endemic in more than 100 countries and it is estimated that annually above 390 million infections occur globally. During the period between 1996–2015, a massive increase of more than 500 per cent has been recorded in number of dengue cases reported in India. Till date, there are no specific globally accepted treatments for dengue fever in any system of medicine. Dengue does not cause very high mortality if properly handled and is currently being managed by clinicians through various adjuvant and alternative therapeutic options. Various plant based preparations have been used in different parts of India for combating dengue and are simultaneously also being scientifically validated by researchers. However, number of such scientific validation studies on phytomedicines are very less in India. Out of twenty-two plants reported against dengue, only four have been studied scientifically. Azadirachta indica, Carica papaya, Hippophae rhamnoides and Cissampelos pareira extracts were found effective and demonstrated improvement in clinical symptoms and direct inhibitory effect on dengue virus. C. papaya clinical trial showed increase in platelet count and faster recovery. These plants may be explored further as probable candidates for drug discovery against dengue. There is a need to search more such herbal formulations, which are being practiced at local level, document properly and validate them scientifically to confirm efficacy, mechanistic action and safety, before use. The herbal formulations being used by communities are the low hanging fruits which may provide alternative or adjuvant therapy if proper validation, value addition and product development steps are followed. This paper aims to review the recent status of dengue cases, deaths and evolving curative herbal solutions adapted and reported from India to combat the disease.

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